Реакция #2346

ord-b36ff282a19946cb9e1721c4f32fd0ac

Условия реакции

Подробные условия
See reaction.notes.procedure_details.

Обработка

  1. 1
    workup.STIRRINGThe mixture was stirred at room temperature for 2 hours
  2. 2
    Температураheated
  3. 3
    Температураat gentle reflux for 21/2 hours
  4. 4
    Другоеevaporated
  5. 5
    workup.ADDITIONThe residue was treated with water
  6. 6
    ДругоеThe gum which precipitated
  7. 7
    Другоеwas separated
  8. 8
    Экстракцияextracted with dichloromethane, (2×50 ml)
  9. 9
    ПромывкаThe combined extracts were washed with brine
  10. 10
    Другоеdried
  11. 11
    Другоеevaporated
  12. 12
    ДругоеThe residue was purified by chromatography
  13. 13
    ПромывкаMega Bond Elut silica gel column, eluting with 5% methanol/dichloromethane/0.5% triethylamine

Методика

A crude sample of the product of Example 36 (3.4 g) was treated with a solution, at 0° C., made by adding thionyl chloride (2.25 g) dropwise to ethanol (45 ml) with stirring at below 0° C. The mixture was stirred at room temperature for 2 hours, heated at gentle reflux for 21/2 hours, and evaporated. The residue was treated with water and adjusted to pH6 with aqueous sodium bicarbonate solution. The gum which precipitated was separated and the aqueous solution was adjusted to pH8 and extracted with dichloromethane, (2×50 ml). The combined extracts were washed with brine, dried and evaporated. The residue was purified by chromatography using a 10 g. Mega Bond Elut silica gel column, eluting with 5% methanol/dichloromethane/0.5% triethylamine to give the title product as a solid (0.2 g); m.p. 163°-165° C.; NMR(CDCl3) δ 8.34(2H,m), 7.97(2H,m), 6.98(2H,m), 6.63(2H,m), 4.89(2H,s), 4.7(2H,s), 4.29(2H,q), 4.1(2H,s), 3.7(2H, m), 3.6(2H,m), 1.31(3H,t); m/e 398(M+H)+ ; calculated for C21H23N3 O5 : C, 63.5; M, 5.83; N, 10.6. Found: C, 61.5; H, 5.9; N, 10.5%.

Источник

DOI: 10.6084/m9.figshare.5104873.v1Патент: US05728701uspto-grants-1998_03